How do I cheaply transfer money from Ireland to Canada for the purpose of student loan payments?

My Situation

I’m Canadian and I took out student loans while studying in Canada. I graduated and started working right away. I have a student loan balance of approximately $29K.

I moved abroad to Ireland. While I don’t know if my move is going to be permanent, it will likely be 10+ years as my spouse is Irish. I need to keep paying my student loans in Canada because my mother is a co-signer of my loans and if I don’t pay, they will go after her for the balance.

My Problem

The National Student Loans Bureau does not accept international payments through foreign institutions. This means I either have to send them bank drafts which have a fee of €7 per draft each month or I have to send the money to my mother’s bank account in Canada for a fee of €15 per transaction.

These extra fees and hassle are making it harder to pay a small extra bit here and there. e.g. if I have €13 hanging around, I can’t just throw it on the loan as sending money overseas is cumbersome.

The interest on my loan has always been very low. A part of it has 0% interest and the rest has 2.45% interest. Currently, there is an interest freeze on the loan.

My options are:

1. send larger bank drafts each month via snail mail (as I get more aggressive with my payments, these could be $1,200 / month)
2. send the minimum payment via snail mail, and then save up the extra bit to send to my mother once per year

The Euro is worth more than the Canadian dollar but sometimes the FX exchange has a fee as well and the exchange fluctuates throughout the year.

What do you think is more efficient and economical?